


Sho'nuff Show U How 2 Tentacle

by smokingbomber



Category: Bishoujo Senshi Sailor Moon | Pretty Guardian Sailor Moon
Genre: Alternate Universe - Merpeople, Anal Sex, Bondage, Choking, Consentacles, Drowning, Explicit Consent, F/M, Face-Fucking, Face-Sitting, I mean if that's actually a vagina, Immortal Endymion, Lemon, Magical anatomy, PWP, Penis In Vagina Sex, Porn With Powers, Rough Oral Sex, Sea Monsters, Serenity is a Pushy Octopus Girl, Spitroasting, Telepathic Sex, Tentacle Bondage, Tentacle Monsters, Tentacle Sex, Vaginal Fisting, being the porn you want to see in the world, brief somnophilia, magical healing, mermaid au, no beta we die like prince endymion, this fic is pure self-indulgent smut, why am i like this
Language: English
Status: Completed
Published: 2021-02-03
Updated: 2021-02-03
Packaged: 2021-03-15 06:46:40
Rating: Explicit
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 4,901
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29184987
Author URL: https://archiveofourown.org/users/smokingbomber/pseuds/smokingbomber
Summary: It's a mermaid AU that's vaguely Silmil-ish and there's no worldbuilding. It's also basically nothing but poor life choices, violence, smut, destiny, and comedy. Apparently Endymion can grow gills if he's desperate enough. Also octopus Serenity is really strong. And Endymion finds out he's really kinky. ¯\_(ツ)_/¯
Relationships: Prince Endymion/Princess Serenity
Comments: 2
Kudos: 16





	Sho'nuff Show U How 2 Tentacle

Endymion did not, as a matter of fact, wake up on the warm and sunny sand of the early morning beach, baking dry in his ripped and sodden tunic. His tunic was at least still on.

He woke up in the process of being dragged back into the water. First he was aware of the sand grinding against his face and trying to get up his nose, and then he noticed it scraping against the rest of his front and mushing his tunic up, and well before he processed anything else at all he kicked back at whatever the hell was dragging him. He _did not need_ the sand to scour anything delicate and he was about to run out of tunic.

Whatever was dragging him stopped, but didn't let go-- instead, it tightened around his ankles, and oh no our prince did not like this at all. He flopped himself over and pushed himself up on his elbows, then squinted. 

"Uh," he started, really intelligently, and then rallied and stopped trying to make sense of what he was seeing. "Hi? Do you speak Common?" he asked, pushing himself up the rest of the way to sitting, and Absolutely Not Panicking about the for-real glowing silver tentacles with his ankles firmly in their cold, wet grips. After all, why should he panic when a painfully beautiful and elfin-looking girl (who happened to have _gills and tentacles and also breasts, how did that even make sense_ ) had him in an iron grip and had been dragging him into the ocean, where he'd probably drown?

Why panic, too, when she was giving him the cutest blank look in the history of ever? Endymion shifted a little, very aware that he had sand in uncomfortable places, and that the water would at least be good for fixing that until he stopped being able to hold his breath. "Okay, no Common. How about High Court? ...Urban Vernacular? Inland Rural Cant? Insular Dialect?" He was starting to get desperate, which at least seemed to amuse the inhuman girl. "Trade Pidgin??"

She brightened -- literally as well as figuratively -- at the last, and answered him in kind, though her voice started out with some awkward gurgling and then a quick turning away to cough-vomit out seawater. "Sorry!" she said, then cleared her throat and laughed. "Chest-air-bags no practice. Trade Pidgin yes! Sailors fruits give, princess sailors no take. You sailor no fruits, no ship. Princess sailor take!"

Endymion ran through that a couple of times in his head, doing his best to parse her interesting grasp of Trade Pidgin. He supposed it wasn't a pidgin with whatever her language was, which ... made sense, because chest-air-bags no practice. "Oh! You're a princess? And... sailors give you fruit so you don't kidnap them?" he asked.

"Yes! You no fruit," she reiterated cheerfully, and leaned forward to pet his foot. "Mine now."

"But I'm not a sailor, I'm a prince!" Endymion protested. "And I don't breathe air. I MEAN. Water. I don't breathe water. I'll drown--"

...but the octo-princess wasn't listening, she was staring at his feet, and poking them much more cautiously now. 

"What-- are you... what--?" fumbled the prince, leaning forward as well, joining her in staring at his foot.

" _Prince_ ," she said and her eyes _gleamed_. "Gold. Land. Healer! Maybe drown. No kill! No mine. Listen, please! Fuck?"

She was giving him whiplash with this stuff.

"What?" he asked blankly, a little breathlessly.

"Fuck!" she repeated, giving him a look like 'are you completely stupid or--?' "Princess fuck, prince fuck?"

"Uh--" Endymion really felt like this was getting away from him. No, that wasn't right. He was positive this had started out away from him and was now a fading dot on the horizon. "Are you propositioning me?"

She pursed her lips and scowled at him, then straightened up and crossed her arms, and, in fact, drew up and up and up on her apparently _very strong appendages_ , and loomed at him. "Yes fuck, or no fuck?" she asked and rolled her eyes.

"I don't even know your name!" said Endymion a little wretchedly; he had very little idea where he was because he hadn't even had a chance to _look_ yet, his ship had _definitely_ gone down and he had no idea if there were other survivors, and he hadn't had any coffee. He was not in control of a single element of this situ--

Wait. No. He was, maybe.

"What would happen if I said no?"

De-looming with a little sploosh and a further coiling up Endymion's ankles to his calves, the octoprincess said, holding a hand to her-- wow and those were really unfairly pretty breasts for someone who was really probably not a mammal, especially given how cold the tentacles on his bare legs were-- holding a hand to her chest, "Serenity. Princess Serenity. You no-say, princess leave. Princess cryyyyy, princess leave--" and it was _so dramatic_ , it was so _overdramatic_.

Endymion raised his eyebrows after giving her a mildly unimpressed look, but taking her response at face value. "What would happen if I didn't like it and I changed my mind?"

And then she grimaced, and reached out to tap his temples with her fingertips. "Uch. Listen here! Not air! Trade Pidgin curse curse."

"Oh, sure, sorry," Endymion said, and opened his mind to her touch, and it was only after he did it that he realized he _never_ just let anyone in like that, and moreover, _she should not have known he was a touch-psychic_ , and by then she was already settling into his thoughts like she lived there. He decided she could live there rent-free, she was so blindingly and shockingly pure. He was a pretty good judge of character, he thought, and definitely knew the signs of an actually manipulative mind, and she didn't have one. She was excited, and she was also horny on main, and really actually would cry but leave if he said no. He could see it, he could feel the little knot of anxiety in her.

 _You're really pretty, Endymion. So is your name! I see the way you write it, it's all curls and loops, I love it. And you have a connection to me you don't know about, and I'd be more than happy to talk to you about it later, but right now, I really just want to rail you until your brain whites out, and I want you to fuck me with your actually legitimately hot-- as in I am cold and you are a living fever-- but also you're pretty-- but anyway fuck me with your hot cock, okay? I'll teach you how! There are definitely at least two places I want you to put it in me. And I want you to do it in the middle of me fucking you into the sea bed. Yes? God please yes,_ Serenity's chiming and bright and graceful whirlpool of a mind's voice dropped directly into his awareness, and therefore also directly into his dick, which was starting to lift up the lap of his tunic.

Endymion's _thoughts_ were circling around variations of GODS FUCK YES NOW PLEASE, and his mouth just sort of hung open in shock.

 _If you change your mind about fucking before we start, I will bring you wherever you want. If you change your mind about fucking while we are deep in transit... hmm. I will have to let you drown, I think,_ she continued, considering him thoughtfully.

He tried to process that, and half of him thought she was kidding, and the other half of him wasn't sure what to think about it, and his expression froze. He didn't want to die.

 _I am not joking, but you will not die,_ she thought more gently. _If you do not want to fuck, and I have to let you drown, you will wake up safe and alone, where your crew can find you. If I have to let you drown but you have not changed your mind about fucking, you will wake up safe but being fucked, and then you can decide if you want me to continue or not._

Oh no, oh he was getting really hard with just the words and demonstration images she was putting in his head, and he thought this was a terrible time to find out he had some wildly unsafe kinks. But she was so confident-- he still kept thinking yes, even as he couldn't make himself say anything. He licked his lips, then opened his mouth again to say something, and he still couldn't make the words happen.

 _Out loud, Endymion,_ the princess told him affectionately. One salty, cold, water-wet tentacle lifted from the tide that was starting to wash over Endymion's legs, and came up to trace his lips. Then it dipped into his open mouth, and it lingered for a moment, then left to encourage him to speak. _Out loud. Since it is how you, Endymion, confirm things, I want to make sure you don't just agree because I am pushy and you are overwhelmed._

"Yes," whispered Endymion, deliberately leaning his face toward the glowing silver tentacle and brushing his mouth against it again, "please, Serenity. I'll believe you. I believe you. Overwhelm me as much as you want." He took a shivering breath. "I'll do my best to return the favor. As soon as you teach me how-- and--"

A deeper breath, and he closed his eyes, but could still see her behind the lids, could still feel her in his mind, and now he showed her deliberately: his responsibilities, his ship, the fate of the crew-- his worries. "--as long as you let me go home."

She patted his face with her hand, then started dragging him back into the water again. In his mind she showed him the wreck's survivors, safe, looking for him. _They can wait. You can go home after. And then you can come back and see me-- you'll miss me. You'll be able to find me. Like I said, we're connected._

Serenity was moving at a good clip, now, propelling them both into the ocean, and by the time she was thinking the word 'connected' at him, he was waving his arms up at the surface, trying to keep his head above it. "Breathing?" he spluttered after saltwater got in his mouth the first time and he bobbed back up.

 _What, already?_ she teased, and he felt her tentacles leave his legs. One wound around his waist and one around his chest, keeping him steady above the water while it got deep enough for her to swim properly in, and then she slowed to transfer him from her tentacles to her arms. _Hold on tight,_ she sparkled at him as she leaned in to kiss him, and then dove under with the human prince clutched tightly to her.

She kept her lovely mouth attached to his, thinking at him that he should open his eyes and avoid breathing through his nose -- oh, and stop holding his breath -- and she filtered carefully into words again instead of just sense impressions. _Breathe from my mouth,_ she instructed him. _I'm sharing with you. It won't go stale, I promise._

Endymion trusted her with his life. She was a strange glowing octopus mermaid princess he'd never met before, but he trusted her with absolute certainty. He did spend a little time examining the fact that he hadn't started entirely trusting her until he let her into his head, but then came to the conclusion that since he'd trusted her enough on instinct to do so, she probably wasn't messing with his mind.

She was a little hurt that he held on to that 'probably', and pulled back from the kiss to crumple her chin at him until she remembered she needed to keep kissing him for now.

He dropped the probably because that wasn't even _subtle_ emotional manipulation, and tried to make the kiss worth her while as he relaxed further into her glowing silver grip. He was aware of the temperature dropping and the pressure rising as she pulled him deeper, and it got darker except for the bubble of light she caused. 

Finally they seemed to be at some sort of destination, and she mentally warned him she was going to stop kissing him, then wrapped one strong tentacle around his ankles and let go of him otherwise. The streamers of her glowing hair floated bright in the water, gradually spreading with the currents and responding like ribbons to her smaller motions, and for a good ten seconds, he held his breath and watched as she moved an enormous stone away from a dark hole in a rock formation. 

Ten seconds, and Endymion started to get nervous, since -- especially at this depth -- it was beginning to get harder not to exhale. He let a bubble out and thought at her, _I'll need to take a breath soon._ He didn't change his mind about fucking, though. He very firmly did not change his mind about fucking.

Since he was only on about air, she ignored him and just continued to hold him by the ankles, unable to kick, and started pulling them into the dark hole. 

_Serenity?_ he thought, letting another bubble out and trying not to let panic bloom from his rising anxiety. _Please, Serenity--_

She turned and regarded him for a half second, then shook her head and turn back, and pulled herself headfirst into the hole. _The faster we get this part over with the sooner you can breathe and we can fuck._ With another one of her tentacles, she picked up a sharp rock and brought it close to Endymion, and that's when his body started panicking without his permission. He thrashed, too-slowly trying to smack the tentacle as it approached him, and another couple of tentacles grabbed his arms by the wrists and wrenched them behind his back. He kept being inexorably dragged into the hole, and at least-- at least-- he could hear her in his head making soothing 'sounds', trying not to get impatient with his biological imperatives. _I'm not giving you air again. I'm going to cut you some gills. You'll be fine if you look at my insides with your power and fix yourself to match. Or you'll drown a lot until -- look, have you changed your mind?_

 _...no,_ thought Endymion, even if now hot saltwater was joining the cold ocean depths, leaking from his eyes. _No. I haven't. But I'm scared._

That's when the tentacle swiftly sliced the rock against his ribcage on either side, then dropped it and wound tightly around his chest. He bled into the water, and his mind shut off in blind panic as the tentacle swiftly squeezed him, hard, and forced out his air. He blankly saw all the bubbles escape as the sharp pain of his ribs cracking added to the wild unpleasantness, and then they were both in the hole in the rock and still moving.

He couldn't stop himself, and the part of him that could still process reality said: Endymion, you are very deep. If she's wrong, you're dead even if you fight her. The rest of his body struggled and _hurt_ , and his golden glow joined her silver in the small, dark tunnel, and his ribs healed, and he tried to study the inner workings of her mystifying body, and her tentacle let go of his chest. He couldn't stop himself, and he took a breath.

The glittering in the edges of his vision was already turning dark, and as it started getting too hard to move and his body began to relax, their combined glows grew dim. The last thing he was aware of was silver tendrils of Serenity's power angrily pulling at his own golden healing, and then everything went away.

* * *

When Endymion woke up again, he was warm and comfortable and had an incredible sense of fullness, there was something in his mouth, and he felt really, really good. No: his body felt really, really-- no, his _dick_ felt really, really, really good. And so did the rest of him.

Then he realized that there was something around his neck, and he couldn't move his arms or legs, and he wasn't breathing -- but there was a silver awareness cradling his, and as the thing in his mouth slipped down his throat and suckers pulled at his tongue in passing, he understood what was going on, he remembered.

He'd drowned after all. That didn't really feel like it mattered, at the moment, and she _had_ warned him-- but there was a tentacle moving down his throat. He wasn't breathing, but he wasn't oxygen-starved: the pressure wasn't too terrible here, in -- oh apparently they were in a glittering cave filled with riches, and one lone tentacle held them both tethered to what certainly looked like a throne -- and he could feel the skin at his sides flexed open, the "gills" she'd cut having turned into something bizarrely functional. He started trying to examine his own body from the inside out--

And then the feeling of fullness _moved_ , and shoved at his prostate and stretched his asshole with a quick flex, and Endymion was abruptly _very_ aware that Serenity also hadn't been kidding when she said she wanted to rail him. There was a warm caressing pressure around his dick, then, and he reflexively tried to gasp. Her silvery mind laughed, a brush of featherlight amusement against his consciousness, and the tentacle around his neck squeezed in a brief embrace before curling around it further, moving to hold his head still. He was very effectively distracted from thinking too hard about the how of this.

The tentacle holding his arms behind his back tightened, and the one around his ankles held fast, and then Serenity bent him in half and looked up, meeting his eyes. His dick was in her mouth. As soon as she was sure he was looking, she bobbed a couple of times, then gave him the mental image of himself, the way she saw him right now, trussed up in her tight grip -- and imagined him thrusting. She pulled him up straight again, the tentacle in his ass driving upwards again and starting to curl, and the one in his throat thrusting down and flexing, driving his head back until he looked like he was swallowing a sword.

Endymion did indeed thrust his hips forward; he felt surrounded by her, and she felt smug and let him know it, and her slender hands caught his hips and held him in place for a second -- then let go so he could thrust again, and again, and she caught him again, and he was already overwhelmed. She held him there, his dick down her throat, and the rest of him held helpless but still able to struggle a little bit, and he was so much more turned on than he'd ever been in his _life_.

Serenity pulled away off of his dick and her tentacles started fucking into him again, in earnest, and she moved up him to cup her hands around the sides of his face and watch his eyes, smiling. Then she moved the bulk of her body up and pulled the tentacle roughly out of his mouth, and relaxed the suckers on the one around his neck and slid it off, uncoiling. She kept a tentacle in his ass, but as she wrapped her arms around his shoulders and moved herself around, she unwrapped the one around his wrists. _How are you feeling, beautiful prince?_ her voice chimed in his mind. 

It took a long, frustrated moment for the prince to gather his thoughts and his twitching body enough to give her a distinct response in their minds, but aside from that 'you PAUSED?' frustration, his reaction was overwhelmingly positive, and he was trying to rally enough to vaguely ask for instructions as to how she'd like him to pleasure _her_.

She bent his legs back at the knees and engulfed most of him with the wide skirt of her body below the waist. _You haven't ejaculated yet. Come. You haven't come yet. You are absolutely going to come inside me before you worry about where you can put your mouth and hands, my pretty prince._

Argue? He wasn't going to argue. He wasn't in charge, and he was okay with that. And then all of a sudden the body engulfing his -- except, carefully, for his neck and his gills -- lined up somehow and squeezed him, and gods of the earth, she had a _tight hole_ in there somewhere and she had just pulled his dick into it. 

His eyes shot open wide and his mouth opened-- he thought, _ahh--!_ sharp and abrupt like a gasp, and she pulled his face to hers with her hand and kissed him hard, and pushed the tentacle in his ass up hard, too, thrusting it deep, deeper. Her body held his legs bent to fit into her constrictive embrace, and his arms tight to his sides, and as she thrust, so did he begin to.

Endymion did his damndest to keep his mind functioning after that pause, that brief recovery, but she was so insistent-- he felt like she might devour him, and that would be all right. She teasingly bit at his lip when he thought it, in the middle of their kiss, and then she bit his tongue hard enough to draw blood and bent him backward, his body arching into it, thrusting faster, struggling like prey. At the same time, she flexed the tentacle in his ass and curled it inside him until it almost hurt, and his entire body stiffened and he came explosively, and he came and came, and they both rode out his orgasm as he did, in fact, white out.

When he was spent, his mouth already healing but his body still twitching, she pulled off of his still-hard cock and thinned the tentacle in his ass so she could pull it out without distressing his oversensitive hole too much. She slid off of him, and gently positioned him with her tentacles, wrapping them around his wrists and ankles again. Another tentacle stroked gently, briefly, over his gills; he shivered, but he was still recovering. 

Serenity kissed him much more gently, careful not to brush against anything she'd just overwhelmed, and then just held him until his gills stopped flaring out so hard, so insistently. She waited until his dick had softened some, and he was more with it, before tightening the grip she had on his limbs a little and demanding his attention.

It wasn't that difficult to get, and she let go of his arms, and his hands immediately went for her breasts. They had _nipples_. This vast mermaid mystery allowed for _nipples_ that could get _hard_ and bring her pleasure if he rolled them between his fingers, if he put his mouth on them, if he suckled. She kept tentacles around his ankles, but indulgently let him explore, let him elicit reactions from her, let him see her twitch and writhe-- just a little-- as his hands trailed down her silver torso and begin seeking the hole under the bell of her lower body, as his fingers found it.

And then a tentacle grabbed the hand that hadn't found the hole and repositioned it, dragging his fingertips across soft and giving tissue until they found something harder, something swollen, and he gently fingered it-- and that's when the hole his other hand was exploring constricted on his fingers, hard and swift, and a bright flash of red light streaked across her silver skin and her mouth opened. This time it was _her_ mind that went _AHhH--!_ and it was Endymion's turn to smirk. 

He popped his fingers out of her hole and gave her a quick mental image, his other hand brushing against that unlikely little nub, and dizzily, she let go of his wrist and curled a tentacle around his neck again, suckers landing where the bruises from earlier were already gone. Endymion's mind laughed warm and golden and bright in hers, and he didn't struggle, letting her just move his body again, letting her put his head under her bell and push his face up against the soft skin down there.

Serenity let go of his wrists, but left the tentacle loosely around Endymion's neck, and one by one started wrapping her other tentacles around him in different places. Around his waist, around his back, around his thighs-- and this time he was awake and pulling what was apparently her clitoris into his mouth when she nudged a tentacle back into his ass. With the one tentacle still tethering them to the throne, she curled the other two around him also, but then let go, and started to just play fitfully with with his body as he began to play purposefully with her very erogenous parts.

His fingers pushed their way back inside, slick with a combination of her and his own spend trickling out. Mouthing at her, scissoring her hole open with his fingers, he discovered he didn't much like the taste of himself. She was still attentive and could tell, so she warned him to keep his mouth closed around her clit and pushed his fingers out, then pushed his cum out as well, and it drifted away and dispersed in the water, waved away by her remaining free tentacles.

As Serenity's hole relaxed open again, Endymion's teeth grazed her clit and she shuddered, tightening briefly around him and mashing his face into her flesh. Her hands closed on nothing, and then she reached out blindly with them and pulled them both toward the throne; taking the arm of it in her hands and whipping her last tentacle free of it. It wrapped around his legs and pulled them up again, and then she had one of the other two join it in keeping his legs tightly bound, and the last pulled up and folded in on itself to pull wildly at his hair, push his head up against her again, more, still--

\--and he started working more of his hand in as his tongue circled round her clit more and more quickly. Three fingers, four-- and then slowly, his whole hand working against the clench of her hole, and he nosed against her and licked, long and rough against her clit and then around the edge of her hole where it met his wrist. He kept pushing; he felt no pain signals from her, and mentally laughed as she tightened the coil around his neck and shoved his head back into position with his mouth on her clit-- and then his arm was inside her up to the elbow, and he carefully spread his fingers against the soft flesh inside and gently bit down, and she came violently all around him, surrounding him and squeezing him convulsively. It hurt, oh it hurt, but it was worth it even as he blacked out thinking she might have cut off his arm, vaguely wondering if she actually crushed him, or maybe his head would come off--

* * *

When Endymion woke up again, there was no blood in the water, no copper tang to the salt in his mouth, in his gills, filling his lungs. He didn't hurt -- of course he didn't hurt, not with the way he healed -- and at least he knew she hadn't accidentally dismembered him. Serenity held him with gentle firmness in her lair, most of her tentacles attached to him and coiled around variously, and her arms held him gently against her, his head pillowed on her breasts.

The princess's chiming mental voice was sleepy and sated and inordinately pleased. _You are very good at fucking,_ she told him, _and at being fucked._ Her whole consciousness smiled indulgently at him, matching the expression on her face when he tilted his head to look up at her.

 _So are you,_ he thought at her, his golden warmth joining her silver brightness in being mutually very, very amused. _If I didn't have responsibilities, I'd actually ASK you to keep me._

 _So you come back to visit me as often as you like,_ Serenity thought reasonably. _I'll get you home later, and you just pay attention to where we go, and what I feel like moving away from you. You'll be able to find me. Keep trusting me, beautiful prince, my Endymion._

 _Oh, I will,_ he answered her with a sleepy feeling that was closer to love than anything he'd ever felt for any human girl. _I will, my absolutely fucking kinky tentacle princess, my Serenity._

After a second, she mentally prodded him expectantly.

 _Beautiful,_ he amended, laughing at her. _My absolutely fucking kinky beautiful tentacle princess Serenity._

She hugged him bodily without squeezing, and then she abruptly decided it was time to nap.

After a long moment, Endymion mentally prodded at her, like tugging her sleeve or nudging her arm. She couldn't _really_ be asleep so fast, could she? _Serenity--?_ he ventured, but her silver mind was a drifting and comfortable abstract. He wriggled, and she tightened around him without waking up.

He supposed another nap wouldn't hurt him, and drifted off in her many, many arms.


End file.
